Pre- and Postharvest Strategies for Pleurotus ostreatus Mushroom in a Circular Economy Approach

Publisher Copyright: © 2024 by the authors.Mushroom cultivation presents a viable solution for utilizing agro-industrial byproducts as substrates for growth. This process enables the transformation of low-economic-value waste into nutritional foods. Enhancing the yield and quality of preharvest edible mushrooms, along with effectively preserving postharvest mushrooms, stands as a significant challenge in advancing the industry. Implementing pre- and postharvest strategies for Pleurotus ostreatus (Jacq.) P. Kumm (oyster mushroom) within a circular economy framework involves optimizing resource use, minimizing waste, and creating a sustainable and environmentally friendly production system. This review aimed to analyze the development and innovation of the different themes and trends by bibliometric analysis with a critical literature review. Furthermore, this review outlines the cultivation techniques for Pleurotus ostreatus, encompassing preharvest steps such as spawn production, substrate preparation, and the entire mushroom growth process, which includes substrate colonization, fruiting, harvesting, and, finally, the postharvest. While novel methodologies are being explored for maintaining quality and extending shelf-life, the evaluation of the environmental impact of the entire mushroom production to identify areas for improvement is needed. By integrating this knowledge, strategies can be developed for a more sustainable and circular approach to Pleurotus ostreatus mushroom cultivation, promoting environmental stewardship and long-term viability in this industry.publishersversionpublishe

The uptake of macronutrients by an active silicon accumulator plant growing in two different substrata

Pennisetum clandestinum (Graminae/Poaceae) an active Si-accumulator, was cultivated in two different substrata, both with reduced Si solubility. Plants growing in organic-rich soils contained much less Ca, K, Na and Si, than species growing in sandy soils. Although the highest macronutrient concentrations were associated to the highest Si levels in the organs of P. clandestinum, the R correlation values indicate that Si does not influence the internal balance and the uptake of these elements. In ca 65% of the cases roots have the highest average values regardless of the type of culture, while the contents of Mg in the shoots and roots of P. clandestinum were generally not significantly different (P>0.05). A significant decline of the macronutrient levels associated to the shoots and roots of P. clandestinum was observed from the 4th to the 6th month assay, especially for Ca in both organs, while for Mg and Na the decline is focused mainly in the shoots; K and Si decline is generally below 10%. When average values of Si in shoots and roots of plants collected from organic- rich and sandy soils were plotted against the average concentrations of Ca, K, Mg and Na in the same organs, weak but positive R correlation values were obtained - the highest R values were observed for Na and K and the lowest for Ca and Mg, regardless of the culture. Exception for the high R value observed for K, although the influence of Si on the K status in the whole plant is time-depending - R values, diminished from the 4th to the 6th month, as it happens in the majority of the cases. In conclusion, P. clandestinum can grow well and healthily in substrata with acid pH values and high carbonate content and low solubility of Si suggesting that the definition of the essentiality of Si, even in a Si-accumulator plant is still a matter of great controversy.publishersversionpublishe

Protective Responses at the Biochemical and Molecular Level Differ between a Coffea arabica L. Hybrid and Its Parental Genotypes to Supra-Optimal Temperatures and Elevated Air [CO2]

Climate changes with global warming associated with rising atmospheric [CO2] can strongly impact crop performance, including coffee, which is one of the most world’s traded agricultural commodities. Therefore, it is of utmost importance to understand the mechanisms of heat tolerance and the potential role of elevated air CO2 (eCO2) in the coffee plant response, particularly regarding the antioxidant and other protective mechanisms, which are crucial for coffee plant acclimation. For that, plants of Coffea arabica cv. Geisha 3, cv. Marsellesa and their hybrid (Geisha 3 Marsellesa) were grown for 2 years at 25/20 C (day/night), under 400 (ambient CO2, aCO2) or 700 L (elevated CO2, eCO2) CO2 L-1, and then gradually submitted to a temperature increase up to 42/30 C, followed by recovery periods of 4 (Rec4) and 14 days (Rec14). Heat (37/28 C and/or 42/30 C) was the major driver of the response of the studied protective molecules and associated genes in all genotypes. That was the case for carotenoids (mostly neoxanthin and lutein), but the maximal (a + b) carotenes pool was found at 37/28 C only in Marsellesa. All genes (except VDE) encoding for antioxidative enzymes (catalase, CAT; superoxide dismutases, CuSODs; ascorbate peroxidases, APX) or other protective proteins (HSP70, ELIP, Chape20, Chape60) were strongly upregulated at 37/28 C, and, especially, at 42/30 C, in all genotypes, but with maximal transcription in Hybrid plants. Accordingly, heat greatly stimulated the activity of APX and CAT (all genotypes) and glutathione reductase (Geisha3, Hybrid) but not of SOD. Notably, CAT activity increased even at 42/30 C, concomitantly with a strongly declined APX activity. Therefore, increased thermotolerance might arise through the reinforcement of some ROS-scavenging enzymes and other protective molecules (HSP70, ELIP, Chape20, Chape60). Plants showed low responsiveness to single eCO2 under unstressed conditions, while heat promoted changes in aCO2 plants. Only eCO2 Marsellesa plants showed greater contents of lutein, the pool of the xanthophyll cycle components (V + A + Z), and b-carotene, compared to aCO2 plants at 42/30 C. This, together with a lower CAT activity, suggests a lower presence of H2O2, likely also associated with the higher photochemical use of energy under eCO2. An incomplete heat stress recovery seemed evident, especially in aCO2 plants, as judged by the maintenance of the greater expression of all genes in all genotypes and increased levels of zeaxanthin (Marsellesa and Hybrid) relative to their initial controls. Altogether, heat was the main response driver of the addressed protective molecules and genes, whereas eCO2 usually attenuated the heat response and promoted a better recovery. Hybrid plants showed stronger gene expression responses, especially at the highest temperature, when compared to their parental genotypes, but altogether, Marsellesa showed a greater acclimation potential. The reinforcement of antioxidative and other protective molecules are, therefore, useful biomarkers to be included in breeding and selection programs to obtain coffee genotypes to thrive under global warming conditions, thus contributing to improved crop sustainabilityinfo:eu-repo/semantics/publishedVersio

Protective Response Mechanisms to Heat Stress in Interaction with High [CO2] Conditions in Coffea spp.

This work was supported by national funds from Fundacao para a Ciencia e a Tecnologia through the projects PTDC/AGRPRO/3386/2012, the research units UID/AGR/04129/2013 (LEAF) and UID/GEO/04035/2013 (GeoBioTcc), as well through the grant SFRH/BPD/47563/2008 (AT) co-financed through the POPH program subsidized by the European Social Fund. Brazilian funding from CAPES (grams PDSE: 000427/2014-04, W.P. Rodrigues; 0343/2014-05, MM; 12226/12-2, LM), CNPq and Fapemig (fellowships to FDM, FP, and EC) are also greatly acknowledged.Modeling studies have predicted that coffee crop will be endangered by future global warming, but recent reports highlighted that high [CO2] can mitigate heat impacts on coffee. This work aimed at identifying heat protective mechanisms promoted by CO2 in Coffea arabica (cv. Icatu and IPR108) and Coffea canephora cv. Conilon CL153. Plants were grown at 25/20 degrees C (day/night), under 380 or 700 mu L CO2 L-1, and then gradually submitted to 31/25, 37/30, and 42/34 degrees C. Relevant heat tolerance up to 37/30 degrees C for both [CO2] and all coffee genotypes was observed, likely supported by the maintenance or increase of the pools of several protective molecules (neoxanthin, lutein, carotenes, ohtocopherol, HSP70, raffinose), activities of antioxidant enzymes, such as superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), catalase (CAT), and the upregulated expression of some genes (ELIP, Chaperonin 20). However, at 42/34 degrees C a tolerance threshold was reached, mostly in the 380 -plants and Icatu. Adjustments in raffinose, lutein, beta-carotene, alpha-tocopherol and HSP70 pools, and the upregulated expression of genes related to protective (FLIPS, HSP70, Chape 20, and 60) and antioxidant (CAT, CuSOD2, APX Cyt, APX ChI) proteins were largely driven by temperature. However, enhanced [CO2] maintained higher activities of GR (Icatu) and CAT (Icatu and IPR108), kept (or even increased) the Cu,Zn-SOD, APX, and CAT activities, and promoted a greater upregulation of those enzyme genes, as well as those related to HSP70, ELIPs, Chaperonins in CL153, and Icatu. These changes likely favored the maintenance of reactive oxygen species (ROS) at controlled levels and contributed to mitigate of photosystem II photoinhibition at the highest temperature. Overall, our results highlighted the important role of enhanced [CO2] on the coffee crop acclimation and sustainability under predicted future global warming scenarios.publishersversionpublishe

Efeitos do Excesso do Cobre em Plantas de Arroz - Aspectos Bioquimicos, Fisiologicos e Ultra-estruturais

Rice (Oryza sativa L. cv. Safari) plants were grown over a 30-day period in a nutrient solution containing increasing Cu concentrations (0.002, 0.01, 0.25, 1.25 and 6.25 mg/l). In total tissues the average concentration of Cu was 35.1 ug/g (dw) Cu at the threshold toxicity a biphasic kinetic pattern was found for Cu up take rates, with a transition phase occurring at metal concentrations between 0.5 and 0.25 mg/l. Although the correlation between Cu and N, P, K, Ca, Mg, Zn, Fe, Mn, B, Mo, Na and Al accumulation might be complex, it seems to depend on its interations at the level of the net uptake rate. In the roots, Cu concentration seems to be related metionine and/or histidine concentrations, in 30 and 8.5 kDa proteins (as well as in 11 and 12 kDa polypeptides in 6.25 mg/l Cu treatment) being immobilized in the vacuoles. In the shoots excess Cu seems to occur in a form or suborgenellar distribution which does no inhibit acid phosphate and cytocrome creductase activities and at least in part, it accumulates in the vacuoles and possibility sticks to the tonoplast. In both root and leaf tissues excess Cu decreases the conversion of SAM to ACC. Concerning to roots it is also suggest that the variations triggered excess Cu on root growth might be explained through the interaction among Cu uptake mechanism(s), plasma membrane H"+ ATPase and root membrane permeability. In the shoots it seems that non lethal toxic copper concentrations stimulate ascorbate, diamine and o-diphenol oxidase activities which might inhibit the biomas production. Furthermore, it was found that increasing Cu concentration decreasing protein contents by affecting acid RNAse activity. The decrease of Mn and Fe concentration (triggered by excess Cu) seems to inhibit the syntesis of PT, PTF and PCh(ide) therefore inducing the decrease of carotenoids and chl concentrations, however, the sharp inhibition of Rubisco as well as inhibition at the level of the antenna chl a molecules of PSII might explain the observed decrease of net photosynthesis. Excess Cu also seems to inhibit the photo-synthetic electron transport mainly before the DPC donation site and, furthermore, decrease the contents of Pc and cyt f, whereas the PQ concentration sharply increased additionally, the leaf capacity for reduction of nitrate to amonia might also be primarily limited by capacibility of the chloroplast photo-chemical reactions to generate reducing power. With Cu levels greater than 0.25 mg7l the poly-peptide bands with apparent molecular weights of 42/41, 33/32, 21/20 and 19/18 kDa decreased. Furthermore, the use of a discontinuous SDS buffer system gel elctrophoresis showed a decreased of the 56/55, 55/54, 26 and 22 kDa bands with increasing Cu concentrations, along with the disappearence of the 16.5, 14.5 and 12 kDa bands. After the 0.25 and 12 kDa bands. After the 0.25 mg/l Cu treatment two bands having pl's 5.5 and 5.18 are replaced by a four different ones (ol's 6.7, 6.05, 5.35, 5.25). Cu toxicity might also block the intrachloroplastic peroxidase system trough a mechanism linked to ethylene biosynthesis. PC, MGMG and DGDG are the membrane components mainly affected by peroxidation which is coupled to an increase of the linolenatehydroperoxide concentrationAvailable from Fundacao para a Ciencia e a Tecnologia, Servico de Informacao e Documentacao, Av. D. Carlos I, 126, 1200 Lisboa / FCT - Fundação para o Ciência e a TecnologiaSIGLEPTPortuga

Pre- and Postharvest Strategies for <i>Pleurotus ostreatus</i> Mushroom in a Circular Economy Approach

Mushroom cultivation presents a viable solution for utilizing agro-industrial byproducts as substrates for growth. This process enables the transformation of low-economic-value waste into nutritional foods. Enhancing the yield and quality of preharvest edible mushrooms, along with effectively preserving postharvest mushrooms, stands as a significant challenge in advancing the industry. Implementing pre- and postharvest strategies for Pleurotus ostreatus (Jacq.) P. Kumm (oyster mushroom) within a circular economy framework involves optimizing resource use, minimizing waste, and creating a sustainable and environmentally friendly production system. This review aimed to analyze the development and innovation of the different themes and trends by bibliometric analysis with a critical literature review. Furthermore, this review outlines the cultivation techniques for Pleurotus ostreatus, encompassing preharvest steps such as spawn production, substrate preparation, and the entire mushroom growth process, which includes substrate colonization, fruiting, harvesting, and, finally, the postharvest. While novel methodologies are being explored for maintaining quality and extending shelf-life, the evaluation of the environmental impact of the entire mushroom production to identify areas for improvement is needed. By integrating this knowledge, strategies can be developed for a more sustainable and circular approach to Pleurotus ostreatus mushroom cultivation, promoting environmental stewardship and long-term viability in this industry

Wheat plant response to zinc enrichment: results from a big plot assay

One third of the global population suffers Zn deficiency, which directly affects their health and the health-bill of all world countries. In this study, the application of Zn sulphate at the latest developing stages (anthesis and milk-dough stages) of bread wheat in Mediterranean conditions were tested for grain and leaves enrichment capacity and antioxidant activities prompting. Variety effects were found to be significant to success in enriching leaves and grains with Zn. While Almansor and Roxo varieties increased more than 50% and close to 40% respectively their amount in grain Zn, no significant differences were found for Paiva variety with or without Zn treatment. Regarding the leaves, Zn amount increases of 110, 230 and 300 ppm of Zn were figured out in Almansor, Roxo and Paiva varieties respectively. Antioxidant compounds in leaves showed to be higher when zinc treatment was applied in Almansor variety. Quality traits of the grain wheat were barely affected by the increase of the Zn amount; Roxo variety grains increased the protein and the dry gluten concentration, while Almansor grains were heavier and Almansor flour showed higher tenacity. It can be concluded that Zn enrichment in wheat plants caused variation in both grain and leaves mineral profile, and antioxidants in leaves.Keywords: Antioxidants, Rainfed conditions, RXF, Winter cereals, Zin

Wheat plant response to zinc enrichment: results from a big plot assay

One third of the global population suffers Zn deficiency, which directly affects their health and the health-bill of all world countries. In this study, the application of Zn sulphate at the latest developing stages (anthesis and milk-dough stages) of bread wheat in Mediterranean conditions were tested for grain and leaves enrichment capacity and antioxidant activities prompting. Variety effects were found to be significant to success in enriching leaves and grains with Zn. While Almansor and Roxo varieties increased more than 50% and close to 40% respectively their amount in grain Zn, no significant differences were found for Paiva variety with or without Zn treatment. Regarding the leaves, Zn amount increases of 110, 230 and 300 ppm of Zn were figured out in Almansor, Roxo and Paiva varieties respectively. Antioxidant compounds in leaves showed to be higher when zinc treatment was applied in Almansor variety. Quality traits of the grain wheat were barely affected by the increase of the Zn amount; Roxo variety grains increased the protein and the dry gluten concentration, while Almansor grains were heavier and Almansor flour showed higher tenacity. It can be concluded that Zn enrichment in wheat plants caused variation in both grain and leaves mineral profile, and antioxidants in leaves.Keywords: Antioxidants, Rainfed conditions, RXF, Winter cereals, Zin